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i am new in programming please help me to solve this problem i have to send a message from and to my own email.

The error is:

The SMTP server requires a secure connection or the client was not authenticated. The server response was: 5.5.1 Authentication Required. Learn more at

What I have tried:

SmtpClient smtp = new SmtpClient("", 587);
            MailMessage mm = new MailMessage("", "");
            mm.Subject = "abc";
            mm.Body = "ansdjfskhfsa d fjk h sjh  sdhf hskd";
            smtp.Credentials = new System.Net.NetworkCredential("", "mypasword");
            smtp.EnableSsl = true;
            TextBox1.Text = "the email is been sended to the reciver";
Updated 26-Jun-17 1:42am
Afzaal Ahmad Zeeshan 26-Jun-17 11:31am    
Just double check, whether your account information is correct and that this is not a new account. Google needs to know that this is you, using the account and not a spammy bot.

Gmail SMTP port (SSL): 465
See: What Are the Gmail SMTP Server Settings?[^]
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You first check your gmail account has two steps verification is on or not. If on then you must off two steps verification.
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